Cobb, jr
fabrication method



T a DEFENSIVE PUBLICATION UNITED STATES PATENT OFFICE Published at therequest of the applicant or owner in accordance with the Notice of Apr.11, 1968, 849 0.G. 1221. Identification is by serial number of theapplication and the heading indicates the number of pages ofspecification, including claims, and of sheets of drawing contained inthe application as originally filed. The file of this application isavailable to the public for inspection; reproduction may be purchasedfor 30 cents per sheet.

Applications published under the Defensive Publication Program have notbeen examined as to the merits of alleged invention. The Patent Oflicemakes no assertion as to the novelty of the disclosed subject matter.

PUBLISHED SEPTEMBER 16, 1969 811,338 FABRICATION METHOD James StanleyCobb, Jr., Martinsville, Va., assignor to E. I. du Pont de Nemours andCompany, Wilmington.

Del. a corporation of Delaware Filed Mar. 28, 1969. Published Sept. 16,1969 Int. Cl. B21k 5/20; D01d U.S. Ci. 76-107 1 Sheet Drawing. 8 PagesSpecification A method of fabricating minute capillaries which extendfrom counterbores in one side to complex, slotted orifices in the otherside of a spinneret plate. Each orifice is segmented and each segmenthas peripheral and radial slots. After forming a countersink of the sameconfiguration as an orifice in the bottom of a counterbore, the radialand peripheral slots are punched in two steps which leave the platedished into the counterbore. Oversized punches are used but uniformslots of the desired size are achieved simply by pushing into thecounterbore with a pin to flatten the area which had been dished in thepunching steps.

DEF. PUB.

Sept. 16, 1969 J. 5. COBB, JR

FABRICATION METHOD Fil ed March 28, 1969

